U.S. Pat. No. 3,600,471 (Haubein I) and U.S. Pat. No. 3,733,406 (Haubein II) disclose phenyl N-dialkoxyphosphinothioacetyl-N-methylcarbamates wherein the dialkoxy radicals are methoxy or ethoxy and the phenyl radical is substituted with one or more substituents selected from the group of lower alkyl, alkenyl, alkoxy, alkenyloxy, or carboalkoxy radicals, chloro, cyano or nitro groups. These dialkoxyphosphinothioacetyl compounds possess only moderate insecticidal and miticidal activity.